Air-supply system for blast furnaces



March 20, 1928. 1,662,851 A. J. EBNER AIR SUPPLY SYSTEM FOR BLAST FURNACES Filed Feb. 14. 1927 Patented Mar. 20, 1928.

UNITED STATES. PATENT o rca ALFRED J. EBNER', OF CHICAGO, ILLINOIS, ASSIGNOR TO FREYN ENGINEERING COM- l PANY, ORCHICAGO, ILLINOIS, A CORPORATION OF MAINE.

AIR-SUPPLY SYSTEMFOR BLAST FURNACES.

Application filed February 14, 1927. Seria1 No. 167,944.

The present invention relates to air supply systems for blastfurnaces.

It is essential that a blast furnace be supplied with air at as uniform a rate as t sible, It is customary to exercise great care that'the source of the air blast, whether reciprocating blowing engines or turbo blowers, deliver air tothe furnace at a constant rate of flow. NVith two or more furnaces in operation, it has been common practice to have each furnace connected to its own individual blast equipment, each furnace with its blowing equipment and connecting blast piping being a separate and-distinct unit. By this practice it is possible to accurately control the volume of air delivered to each furnace bycontrolling the speed of the blowing unit. The practice of providing separate blowing units for each furnace is i1 expensive in view of the fact that a large number of blowers has been required, which has involved a large num'ber of auxiliaries, such as condensers, pumps, piping, airintake tunnels, a large amount of foundation work, large buildings, and a large number of mains.

An object of the present invention is to provide an efficient system in which, in a. plant employing two or more furnaces, wind is taken from a blast main common to all of said furnaces.

A further object is to provide a system employing two or more furnaces in which wind is taken from a common source and delivered to each of said furnaces in constant volume regardless of variations in the working condition of each furnace and regardless of variations in the working conditions between said furnaces.

A further object is to provide a system employing two or more blast furnaces in which each furnace is provided with a con stant volume control and in which a single blast source will be controlled to suit con ditions.

Further objects will appear as the de scription proceeds.

Referring to the drawings- The one figure of the drawing is a view illustrating the principles of the present invention, the number of furnaces being supplied with air being the same as the layout illustrated in the figure.

The improved system disclosed in th drawing shows furnaces 11, each conposin the drawing itwill be necessary to carry nected through a corresponding pipelineQv to its individual set of.stoves 33, cachindividual set of stoves being connected to the corresponding pipe line 4. Each of the pipe lines 4 is connected to the main 9, which main is supplied by a blast supply unit indicated by the numeral 10. Said blast unit- 10 mayconsist of one or more blowers. In thediagrammatic showing of the drawing, three blowers 11l1 are illustrated, which blowers operate in parallel, veaclrbeing con nected to the main ,9 through a pipe '12 con trolled by the manually operable valveldi.

According to the systemillus-tratedvin the drawing, the motive the blowers 11-11 is derived from thesteani line 14, which is connected to the driving means for the blowers 1111 through .the manually operable valves 15-15'. Connected in series relationship witheach of the manually operable valves 1515 is a control valve 16. Each of saidcontrolval-ves 16. is responsive to .the pressure regulator 17, which pressure regulator is, responsive to the pressure within the main 9.

Each of the blast lines 4lf is provided with the volume regulator 18, which has the function of maintaining a constant volume of air to the blast furnace 1, regardless of variations in working conditions of its corresponding blast furnace and regardless of variations in working conditions between the various blast furnaces 1-1.

In the operation of the system disclosed the pressure in the blast main 9 at or slightly in excess of the pressure demanded by the furnace with the greatest blast resistance. The present invention contemplates a coordination of the pressure regulator 17 with the separate constant volume controls 1818, whereby the blast pressure upon each furnace 1 will be built up or reduced to suit the furnace of maximum pressure demand. Operation of the pressure regulator 17 will result in operation of the control valves 16-16 to control the supply of steam to the driving means for each of the blowers 1111 to effect the proper speed regulation of said blowers. Manual operation of the system is also possible by reason of the manually operable valves 1515.

Bythe improved system illustrated in the drawing, considerable savings are effected in plant construction and operating costs.

power for driving H of a single unit comprising three blowers (which number may be reduced if desired) to operate a four-furnace plant. vVith three blowers, as shown in the drawing, two of the blowers would be operated and would have a combined capacity to blow all four furnaces, while one would be a spare, affording a fifty per cent protection. In case it were preferred to install the two blowers, each would have sufficient capacity to blow all of the furnaces, while the other would be a one hundred per cent spare. A very considerable saving results in the system disclosed in the drawing over the conventional system, by reason of the lesser number of blowers, the lesser number of connected auxiliaries such as condensers, pumps, piping, air intake tunnels and the like, less foundation work, smaller buildings, and the provision of one common blast main against a number of separate mains leading to the individual furnaces.

Though one embodiment of the present invention has been indicated diagrammatically, many modifications will occur to those skilled in the art. It is intended to cover all such modifications that fall within the scope of the appended claims.

What is claimed is- 1. In a blast furnace system, a plurality of blast furnaces, conduit means for supplying air to each of said furnaces, each of said conduit means being provided with a volume regulator for controlling the rate of air supply to its corresponding furnace, a

common blast mam for delivering air to said regulating means, an air supply unit,.and means responsive to the pressure within said blast main for controllingsaid air supply unit. 7 i

2. Ina blast furnace system, in combination, a plurality of furnaces, individual means for supplying air to each of said furnaces, a common blast main connected to said air supply means, each of said air supply means being provided with a volume regulator, and means for regulating the pressure of air delivered to said blast main,

3. In a blast furnace system, in combination, unitary air supply means, means for maintaining constant the air pressure therein, and a plurality of furnaces supplied by said unitary air supply means,reach of said furnaces having operatively associated therewith regulating means forcontrolling the volume of air delivered to each of said furnaces.

Signed at Chicago, Illinois, this 11 day of Febn, 1927.

ALFRED J. EBNER. 

